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521.
Namar Mohamad Mostafa Jahanian Omid 《Journal of Thermal Analysis and Calorimetry》2019,137(1):205-215
Journal of Thermal Analysis and Calorimetry - Nowadays, engines design technology tends toward less fuel consumption and emission besides higher efficiency. Hydrogen as a clean fuel has been a... 相似文献
522.
Mohidem Nur Atikah Bin Mat Hanapi Mohamad Mardawani Hamzah Fazlena Rashid Muhammad Usman 《Journal of Sol-Gel Science and Technology》2021,98(3):462-469
Journal of Sol-Gel Science and Technology - Oxidoreductases are widely recognized for their capability to degrade phenolic pollutants and versatile. However, the lack of enzyme stability makes this... 相似文献
523.
Safaei Somayeh Kassaee Mohamad Zaman Khorshidvand Neda Ahmadi Aliakbar 《Research on Chemical Intermediates》2020,46(10):4359-4381
Research on Chemical Intermediates - Laetrile (D-mandelonitrile-β-D-glucuronic acid, 1COOH) is being promoted, more and more, as an alternate cancer treatment, in many countries. Here we show... 相似文献
524.
Nor Atiqah Ismail Shabnam Bakhshaei Muhammad Afzal Kamboh Ninie Suhana Abdul Manan Sharifah Mohamad 《高分子科学杂志,A辑:纯化学与应用化学》2016,53(10):619-628
The present study describes the synthesis and characterization of titania-silica mixed imidazolium based ionic liquid (Ti-Si-IL) as well as evaluation of its adsorption behavior towards the 2,4-dinitrophenol (2,4-DNP) and 2,4,6-trichlorophenol (2,4,6-TCP). Synthesized Ti-Si-IL adsorbent was characterized by Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), BET surface area Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA) and elemental analysis (CHN). The adsorption of 2,4-DNP and 2,4,6-TCP on Ti-Si-IL was investigated systematically by evaluating the effects of adsorbent dosage, initial pH, contact time and temperature. Satisfactory adsorption 95% and 65% for 2,4-DNP and 2,4,6-TCP was observed at pH 4 and 6, respectively. The kinetic results for 2,4-DNP and 2,4,6-TCP on Ti-Si-IL indicated that the kinetic data follows pseudo-second-order model (R2 = 0.9985 and 0.9750, respectively). Adsorption isotherms were fitted well by the Langmuir model for 2,4-DNP (qm = 44.64 mg g?1 at 318 K) and Freundlich model for 2,4,6-TCP (KF = 0.63 mg g?1 at 318 K). The +ΔH° and -ΔG° values demonstrated that the adsorption of 2,4-DNP was endothermic and spontaneous in nature. While the -ΔH° and +ΔG° values for 2,4,6-TCP adsorption demonstrated exothermic and comparatively nonspontaneous. During the removal process, the role of different functional groups, cyclic structure was monitored and found that the ionic property as well as π-π interactions of host molecules played important role in the extent of adsorption. 相似文献
525.
526.
Nathalie Younan Mohamad Hojeij Lydie Ribeaucourt Hubert H. Girault 《Electrochemistry communications》2010,12(7):912-915
Capacitance measurements of a polarised liquid|liquid interface show that the capacitance of the interface increases in the presence of an adsorbed monolayer of citrate-coated gold nanoparticles. This unusual observation can be explained by an increase of the interfacial charge density or by an increase of the interfacial corrugation. This study shows that capacitance measurements provide a method to monitor metallic film formation at ITIES. 相似文献
527.
Jo-Chun Kim Youn-Suk Son Ki-Joon Kim Yong-Jae Lim Sang-Gwi Chung Young Sunwoo Mohamad Al-Sheikhly 《Radiation Physics and Chemistry》2010,79(7):797-802
We enhanced the decomposition and the removal of toluene in gas phase using a combined method that consists of electron beam (EB) irradiation and catalytic oxidation. The catalytic oxidation system comprises oxidizing particles of 0.1 wt% Pt or 0.1 wt% Pd deposited to supporting materials, which were also used as adsorbents. These adsorbents—supporting materials are Cordierite, Y-zeolite, and γ-alumina. We demonstrated that 100% removal of toluene can be achieved using approximately 9 kGy of dose level in the presence of Pt or Pd deposited to 12 wt%. The G (-toluene) values were determined to be 0.498 and 0.829 μmol/J in the absence and presence of these catalysts with adsorbents, respectively. We have also demonstrated that the presence of the oxidation-catalyst prevents the toluene from undergoing radiolytic polymerization. 相似文献
528.
Najat Ahmed Al-Odaini Mohamad Pauzi Zakaria Mohamad Ismail Yaziz Salmijah Surif 《Journal of chromatography. A》2010,1217(44):6791-6806
Pollutants such as human pharmaceuticals and synthetic hormones that are not covered by environmental legislation have increasingly become important emerging aquatic contaminants. This paper reports the development of a sensitive and selective multi-residue method for simultaneous determination and quantification of 23 pharmaceuticals and synthetic hormones from different therapeutic classes in water samples. Target pharmaceuticals include anti-diabetic, antihypertensive, hypolipidemic agents, β2-adrenergic receptor agonist, antihistamine, analgesic and sex hormones. The developed method is based on solid phase extraction (SPE) followed by instrumental analysis using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC–ESI-MS/MS) with 30 min total run time. River water samples (150 mL) and (sewage treatment plant) STP effluents (100 mL) adjusted to pH 2, were loaded into MCX (3 cm3, 60 mg) cartridge and eluted with four different reagents for maximum recovery. Quantification was achieved by using eight isotopically labeled internal standards (I.S.) that effectively correct for losses during sample preparation and matrix effects during LC–ESI-MS/MS analysis. Good recoveries higher than 70% were obtained for most of target analytes in all matrices. Method detection limit (MDL) ranged from 0.2 to 281 ng/L. The developed method was applied to determine the levels of target analytes in various samples, including river water and STP effluents. Among the tested emerging pollutants, chlorothiazide was found at the highest level, with concentrations reaching up to 865 ng/L in STP effluent, and 182 ng/L in river water. 相似文献
529.
Mohamad Jaber Al-Jeboori Amar H. Al-Dujaili Alyaa E. Al-Janabi 《Transition Metal Chemistry》2009,34(1):109-113
The Schiff base N-crotonyl-2-hydroxyphenylazomethine HL, derived from the reaction of acrylamide and salicylaldehyde, was synthesised. Polymeric
complexes were obtained from the reaction of polymeric HL with divalent metals. The mode of bonding and overall geometry of
the complexes were determined through physico-chemical and spectroscopic methods and compared with that previously reported
for the analogous monomeric ligand. These studies revealed tetrahedral geometries around the metal centres for Mn(II), Co(II),
Zn(II), Cd(II) and Hg(II) complexes of general formula [M(L)Cl], octahedral for Ni(II) and Cu(II) complexes of general formula
[M′(L)Cl(H2O)2], and square planar for Pd(II) complex of general formula [Pd(L)Cl]. 相似文献
530.
Stéphane Laville Christian Goueguel Hakim Loudyi François Vidal Mohamed Chaker Mohamad Sabsabi 《Spectrochimica Acta Part B: Atomic Spectroscopy》2009
The combination of the laser-induced breakdown spectroscopy (LIBS) and laser-induced fluorescence (LIF) techniques was investigated to improve the limit of detection (LoD) of trace elements in solid matrices. The influence of the main experimental parameters on the LIF signal, namely the ablation fluence, the excitation energy, and the inter-pulse delay, was studied experimentally and a discussion of the results was presented. For illustrative purpose we considered detection of lead in brass samples. The plasma was produced by a Q-switched Nd:YAG laser and then re-excited by a nanosecond Optical Parametric Oscillator (OPO) laser. The experiments were performed in air at atmospheric pressure. We found out that the optimal conditions were obtained for our experimental set-up using relatively weak ablation fluence of 2–3 J/cm2 and an inter-pulse delay of about 5–10 μs. Also, a few tens of microjoules was typically required to maximize the LIF signal. Using the LIBS–LIFS technique, a single-shot LoD for lead of about 1.5 part per million (ppm) was obtained while a value of 0.2 ppm was obtained after accumulating over 100 shots. These values represent an improvement of about two orders of magnitude with respect to LIBS. 相似文献